Image forming apparatus and storage medium

Abstract

An image forming apparatus includes an image holder, an intermediate transfer body, a transfer member, a pressing force changer, and a hardware processor. The intermediate transfer body includes a base layer and a coating layer provided on the base layer. The image forming apparatus transfers a toner image formed on the image holder to a sheet via the intermediate transfer body, thereby forming an image on the sheet. The transfer member is provided so as to face the image holder with the intermediate transfer body in between and forms a nip part with the image holder. The pressing force changer changes pressing force of the transfer member against the image holder. The hardware processor controls, with the pressing force changer, the pressing force of the transfer member against the image holder based on information on a surface profile of the sheet on which the image is to be formed.

What is claimed is: 
     
         1 . An image forming apparatus comprising:
 an image holder,   an intermediate transfer body that includes a base layer and a coating layer provided on the base layer, and via which a toner image formed on the image holder is transferred to a sheet, so that an image is formed on the sheet;   a transfer member that is provided so as to face the image holder with the intermediate transfer body in between and forms a nip part with the image holder;   a pressing force changer that changes pressing force of the transfer member against the image holder; and   a hardware processor that controls, with the pressing force changer, the pressing force of the transfer member against the image holder based on information on a surface profile of the sheet on which the image is to be formed.   
     
     
         2 . The image forming apparatus according to  claim 1 , wherein in response to the sheet being uneven paper, based on the information, the hardware processor makes the pressing force of the transfer member against the image holder smaller than the pressing force thereof for the sheet being plain paper. 
     
     
         3 . The image forming apparatus according to  claim 1 , wherein in response to the sheet being uneven paper, the hardware processor makes the pressing force of the transfer member against the image holder smaller as a vertical length of a depressed portion or a raised portion of the sheet is longer, the vertical length being the information. 
     
     
         4 . The image forming apparatus according to  claim 2 , wherein the hardware processor makes tension of the intermediate transfer body smaller as the hardware processor makes the pressing force of the transfer member against the image holder smaller. 
     
     
         5 . The image forming apparatus according to  claim 2 , further comprising a mover that moves the transfer member along a moving direction of the intermediate transfer body, wherein
 with the mover, the hardware processor adjusts, upstream in the moving direction, a position where the transfer member is pressed against the image holder according to the pressing force of the transfer member against the image holder.   
     
     
         6 . The image forming apparatus according to  claim 1 , wherein the hardware processor reduces the pressing force of the transfer member against the image holder and increases current that flows the transfer member. 
     
     
         7 . The image forming apparatus according to  claim 1 , wherein
 the image holder includes a plurality of image holders provided on an outer circumferential side of the intermediate transfer body along the moving direction of the intermediate transfer body, and   the image forming apparatus further comprises a metal blade that is provided upstream from the plurality of image holders in the moving direction and slidingly contacts a surface of the intermediate transfer body.   
     
     
         8 . The image forming apparatus according to  claim 1 , further comprising a lubricant applier that applies a lubricant to an outer surface of the intermediate transfer body or to a part that contacts the outer surface of the intermediate transfer body. 
     
     
         9 . The image forming apparatus according to  claim 8 , wherein the hardware processor controls, based on the information, an amount of the lubricant that is applied by the lubricant applier. 
     
     
         10 . The image forming apparatus according to  claim 1 , wherein the hardware processor performs a removal process for removing a matter adhering to the intermediate transfer body before the image is formed on uneven paper as the sheet. 
     
     
         11 . The image forming apparatus according to  claim 10 , wherein the hardware processor performs, as the removal process, operation of rotating the intermediate transfer body. 
     
     
         12 . The image forming apparatus according to  claim 10 , further comprising a cleaner that is provided downstream from a position where the toner image is transferred to the sheet and upstream from a position where the toner image is formed on the image holder, wherein
 the hardware processor performs, as the removal process, operation of sending a toner band to the cleaner for the intermediate transfer body.   
     
     
         13 . The image forming apparatus according to  claim 1 , wherein the coating layer includes an inorganic oxide to which an organic component is added. 
     
     
         14 . A non-transitory computer-readable storage medium storing a program that causes, of an image forming apparatus including: an image holder, an intermediate transfer body that includes a base layer and a coating layer provided on the base layer, and via which a toner image formed on the image holder is transferred to a sheet, so that an image is formed on the sheet; a transfer member that is provided so as to face the image holder with the intermediate transfer body in between and forms a nip part with the image holder; and a pressing force changer that changes pressing force of the transfer member against the image holder, a computer to:
 control, with the pressing force changer, the pressing force of the transfer member against the image holder based on information on a surface profile of the sheet on which the image is to be formed.